FAST "esc" control

[Glen]

Roland, here is a trouble tree to help. After reading the posts, first thing is to check the connector @ the ECM, both male and female. Ck continuity on H1 from the knock module to the harness connector @ the ECM, but not by back probing, we want to check the integrity of the harness connectors and eliminate it as a problem, so we want to check it where it connects to the ECM, the bent connector thing. I don't have my FAST wire diagram handy so I am ASS U MING that H1 is the signal return to the FAST ECM.
Use digital multimeter when testing

1) * Connect Tach
* Engine running @ about 1500 RPM
* Trans in Park or Neutral and engine @ operating temp
* Tap engine block in area of Knock sensor and check for
RPM drop

NO RPM DROP RPM DROP
Continue to # 2 So whats the problem?

2) * Engine idling
* Back probe terminal H1 w/a voltmeter to ground and note
voltage

UNDER 6 VOLTS OVER 6 VOLTS

3) * Ignition 'ON' Engine STOPPED Faulty connection
* recheck voltage @ H1 @ ECM or bad ECM

UNDER 6 Volts OVER 6 VOLTS

4) * Ignition 'OFF' Replace ESC module
* Disconnect ECM harness
* Ignition 'ON'
* Recheck Voltage

UNDER 6 VOLTS OVER 6 VOLTS

5) * Disconnect ESC module. Replace ECM
* Check voltage from ESC
connector terminal 'B'
to ground
* Should read battery voltage

OK NOT OK
6) * Check for open or short to ground Repair OPEN in
in H1. If not open to ground, circuit "B"
it is a FAULTY ESC connection
or ESC Module

This is GM generic as I can make it. If you need more exact, lemme know. Like if the knock module for a Syclone is wired different.

 

[Roland Black]

Tonites efforts:

I pulled out the wire at H1, cut off the connector and installed a new one. I put it all back together, turned on the ignition, brought my laptop on line with C-Com and hit f9. I then grounded the H1 lead and no recording on my laptop! (insert swear words here) I even recorded a run and still no signal, except for Caspers gauges going off during both operations.

I then took a different laptop, loaded C-com onto it and connected it up to the truck. I went thru the above steps, and no difference........ no ESC signal when H1 was grounded, but the gauges worked. I knew this was going to be a waste of time, but I'm getting desperate here.

I'm now going to try and borrow some locals FAST box to see if it will acknowledge the ground. I've no idea who....... Dennis has his box in being converted to sequential, and I'm unsure if Geno is B2B or not. This conversation is gonna go well.... "hey, how are ya? Can I borrow your FAST ECU for about an hour some day when you aren't driving your Buick? LOL

Until I can get my laptop to show that the FAST ECU is recognizing the ground and doing something about it, I don't see much sense in trying to do much else.

THANKS Glen,

 

[Craig Smith]

Forgive me for even asking this, but how are you determining that the knock sensor isn't activating in the FAST? There are two ways to tell, 1) the "Spark (BTDC)" sensor will begin to drop as the knock retard comes in, and the "ESC Retard" sensor will begin to increase towards the max ESC retard you have programmed in.

This is odd, that's all I have to say. I really expected to find out that there was a cracked resistor or something. But this is a pretty straightforward deal, it either works or it doesn't. There isn't any "kinda working" or "in between" stage. Like the tech that checked it out said to me, "I can't argue with a stop sign."

Sorry for the dumb question I opened with but I'm pretty baffled at this point.

 

[Roland Black]

hey Craig;

I'm watching the ESC retard (*)....... it just sits there at 00.

Don't believe this matters, but all testing is done with key on, but truck NOT running. Makes no difference if I watch "all sensor" screen, or record a run with the ESC retard as one of my 8 sensors selected. It never shows any reading other than the 00. Matter of fact, it NEVER has (even with motor running) With some previous audible knock and no FAST or Casper's response, that is what started this quest.

Your question wasn't dumb by me....... you won't believe the number of times I sat there thinking "what in the hell am I doing wrong"?

Perhaps my buddy Geno (if his is a B2B sys) will allow me to install it and see if his unit makes a difference. At the moment, I can't think of much else to try. Thanks for "thinking",

 

[Craig Smith]

That might matter, actually. Some things don't function in crank mode and that might be one of them.

Try putting the wire directly to ground with it idling and see what happens...

 

[Roland Black]

RED FACE.....

Looks like I take the "dummy of the week award". The ESC retard works nowwith the motor RUNNING when grounded at H1, but I didn't hear Caspers audible gauge going off. I'm unsure if the led's lit up or not as I was SOOOOO excited watching the ESC retard do something, that I never checked. I'll do that tomorrow.

THANK YOU Craig, at last I feel as though I'm starting to get a handle on this. <----- wow, progress! OK, back to red face mode.

YOU BE MY HERO......

 

[Glen]

Thanks CRAIG? Did you not READ my last reply, step #1 ENGINE RUNNING @ 1500 RPM? Key word RUNNING?

 

[Craig Smith]

How about we split the reward money Glen?

 

[Roland Black]

THANKS GLEN!

I didn't have motor running as I was checking for a ground signal at the ECU, not tapping on the motor near the knock sensor and checking for RPM drop. Obviously (now) that was wrong. When I report back with further testing and findings, just respond back to me in BOLD print ;-)

I'll still use your trouble tree as I believe there still is a problem in the system elsewhere, in that other than last nite, it has never recorded ESC retard.

Sure glad running was emphasized otherwise I'd still be doing the same thing with the same results. I ass u med that "all sensors" show timing, water temp., etc. that there was no need. Oh well, shows ya what little I know.

K, guys..... the divided up reward money is in the mail. Thank goodness I don't have to ask someone if I can borrow their ECU for a couple minutes. Thanks again all,

 

[Roland Black]

Ok Glen, I'm seeking your advise please.

With dig. multimeter, I came up with the following (#'s correspond to 'ur trbl. tree)

2. 9+ volts
3. 9+ volts
4. 10+ volts
5. key on.... 12+ volts
6. tests ok.... a ground at pin c (with motor RUNNING=) sets off Casper's and I see it register on FAST ESC retard.

The printed out chart you e-mailed me is sorta run together and I'm unsure exactly which direction this is pointing me. With #2, over 6 volts say faulty ECM connection (which we now know is good) or faulty ECM (which we also now know is good) #3 says over 6 volts, replace ESC module. I did with a new one, and my voltage readings throughout the tree are almost identicle.

I appreciate the assistance, and thanks in advance.

 

[Glen]

First, Knock is different from Ping. Knock sensor will not detect Ping. Second, Module and Sensor HAVE TO BE SAME MAKE, MODEL, YEAR.

Module Wiring
A) Empty
B) 12 Volt (+) Use old ECM/IGN fuse from fuse panel
C) Signal to ECM
D) Ground (-)
E) Signal FROM Knock Sensor

Distr. Wiring
A) EST
B) Ref Hi
C) By-pass - Used for setting timing
D) Distr Return

Now, if you are using a external mount coil from the FAST harness
A = D
B = C
C = B
D = A

In other words, with a Coil in Cap Distr, just plug it in directly as shipped. With the Remote Mount Coil, leaving the FAST harness connector as shipped, take the lead (connector) from the distr and reverse their order to match the above.

Ok, on to the ESC.
Terminal B with Key On Engine Off (KOEO) and Key On Engine Running (KOER) we want 12 Volts Positive (+)

Terminal C - we want to check continuity from the connector terminal to terminal H1 from the pin sides.

Terminal D - We want 12 Volt Negative (-) @ all times

Terminal E - Check continuity to Knock Sensor

Note - Knock Sensor sends an AC signal

KOER Measure voltage on (C). KOER, with hammer, tap engine block on solid surface, not tin, observe voltage drop on terminal C to ECM H1. If need be, measure @ Module and ECM, by back probing. This should also coincide with a Knock detect from the ECM.

If voltage drop is observed and detected by ECM and no RPM drop, observe timing @ crank with Timing Light, note timing w/o knock, then tap on block and observe timing again. If still no timing change, suspect either ECM or IGNITION MODULE.

If NO voltage drop is observed on terminal C of ESC module, ensure connector is good. Using DIGITAL Volt Ohm meter, set volts to AC. Back probe terminal E, of ESC module, positive lead to E and negative lead to ground, again tap block and watch for AC voltage. If we have AC voltage and no output on terminal C, suspect ESC module. If no AC voltage suspect Knock Sensor and ensure it is grounded and fitted tightly in block to detect audible knock. The Knock Sensor may also be removed from vehicle and bench tested for signal, this is best done using an AC wave form.

 

[Roland Black]

hey Glen;

Just a quick response to your note. I'll try and do further testing tomorrow.

My Syclone has the PTE harness for FAST, and the stock Syclone knock sensor, as I wasn't given one with the harness or Buick style module. <--- Should I order a Buick one? (others have told me no) With the harness, my stock ECM was removed, and the PTE harness plugged into the removed connectors. Only connectorizing I did was for WB02, and new injector harness.

Now for the part that is confusing me..... Distr. Wiring:
I have the GM HEI with external coil, along with a Crane Hi6 digital CD unit. Please excuse the ignorance here, but you'r saying I should go the dist., pull off the 4 wire plug in and re-connect the leads in reverse order? I'm NOT following as to why I want to do that. Please explain further. Please keep in mind, this PTE harness is Syclone/FAST specific.

On the module, it is wired as you stated, and all leads are correct with regards to voltage or ground. I have continuity on all wires (sensor to module, and module to ECU) I have checked the sensor with a digital volt meter set on 2vac, and got a reading while tapping on the block. I have not yet tried reading the voltage at terminal E of the module, but will do so tomorrow.

The rest of the testing makes sense to me. However, I'm lost with regards to the distributor wiring, as mentioned above. THANKS again for your time and patience,

 

[Roland Black]

some progress made today.....

Knock sensor connector was bad. I replaced it and now have ac voltage coming out of sensor and into wiring. However, I do not get the signal at the module connector E. I probed the wire lead to E thru the skin just before the connector, and can get a voltage reading tapping on the block. However, just an inch further at the actual connector, no voltage when tapping on the block.

So far, I haven't fiqured out how this connector comes out of the harness.

 

[Roland Black]

I have made some progress but am unsure of where I'm at!

I have a volt meter at the back pin of H1. I read voltage with the key on and running. I go out and tap on the block and I see voltage drop (small, but a drop), but Casper's gauges do not go off, nor does FAST show ESC retard.

I'm confused as the above is doing what I understand it should do, but why no showing elsewhere? Is everything now fine, and it just that there isn't enough actual knock to set things off?

 

[Glen]

Thats good. Now, do the module and knock sensor match same make, model and year? Again, this is important. Supposedly knock sensors match the acoustics of the motor, can't verify this, but this has come up at other places, and the Knock Module is sensative to it's own sensor. But don't hold me to this. Two choices, First, contact FAST and find out what the voltage should be to the ECM. We know the factory ECM works off 6 volts, have no data for the FAST, Second, get Module and Sensor for '90 S/T model 4.3.

I see it as ' we have a signal, it's just weak', and we now have to determine why.

A knock sensor has 2 'ceramic unobtainum' rods with wire wraped around them with a magnet in the middle. These rods vibrate when they sense a certain frequency given off during knock. The vibration and strength generate a AC volt around the magnet which goes to the module. That is why they have to match the motor and module. That how I was learned it. Well that...... and a big stick

 

[Roland Black]

I think it's resolved....

Upon startup, I light up Caspers leds to the middle of the orange. It's NEVER done that before (never got past the first green led when key was turned on, and nothing upon cranking). There is no ESC retard, and the audible didn't go off, but I believe that is due to not enough of a "true" knock signal to FAST. With the above, I know that the signal is getting through....... finally.

Regarding the knock sensor being Buick specific Glen..... most people including John Spina say no biggy. At present I'm also of that belief..... but keep in mind that I didn't see why motor had to be running to record a ESC signal (red face) either.

A really BIG thanks to GLEN and what was his name @ FAST? (thanks Craig =)

 

[Roland Black]

Last and final word;

IT WORKS! With my current tune, I got after it and around 11 psi it lit up like a Christmas tree. Audible screaming in my ears and the leds ablaze. That's the good news.....

The bad news is I have lotsa knock. Oh well, a couple hours of tuning "should" resolve that. Thanks again for the big assist guys,